Re: Any restrictions on engines?
 

A steam or sterling engine would burn some material which would then heat water. On the other hand, I do like the idea of a pressure change being used to do work as part if the definition. That's probbably a more widely acceptable definition.

Re: Any restrictions on engines?
 

I agree that the chemical energy to mechanical energy definition is flawed. I think that in general an engine converts thermal energy into mechanical energy, but then again that may be just a heat engine.

Re: Any restrictions on engines?
 

The best explanation I've seen basically goes as follows:

All engines are motors, but not all motors are engines.

To be an engine, it must be a machine/mechanism (i.e., moving parts) that serves as an energy source.

Examples:

Electric Motor - It has moving parts, but the energy source (the battery) is not part of it, thus it isn't an engine.

Combustion Engine - It has moving parts and gasoline is burned inside, therefore it IS an engine.

Solid Rocket Motor - It serves as an energy source (burning fuel inside of itself), but it has no moving parts, thus it isn't an engine.

Liquid Rocket Engine - It serves as an energy source (burning fuel inside of itself), and there are tons of moving parts (turbomachinery), therefore it IS an engine.

Re: Any restrictions on engines?
 

I love how the trolling thread has been derailed into something useful.

Let's make a list:
Motors
Electric motor
Rocket motor
Molecular motor
Motorcycle
Motor neuron

Engines
Gasoline engine
Jet engine
Steam engine
Stirling engine
Search engine

I remember reading a model rocketry book which was adamant that the propulsion was a "rocket motor", and not a "rocket engine". But I see now that Estes calls them "engines".
Wikipedia treats "motor" and "engine" as effectively synonymous, at least until someone here goes and edits the article.

Re: Any restrictions on engines?
 

A rough rule of thumb I have heard for rockets is that solid and hybrid rocket engines can be called motors without anyone looking at you funny. However a liquid rocket engine cannot be called a motor without someone raising their eyebrows.

All I know is I have an outboard engine on my motorboat... :rolleyes:

Re: Any restrictions on engines?
 

Yeah, Estes is wrong. My rocket propulsion professor was equally adamant about solids being a "motor" (I'll take his word for it. He basically wrote "the book" on solid rocket motors)

Re: Any restrictions on engines?
 

I'm betting FIRST will allow you to choose between a search engine or a siege engine. I'm digging siege engines. We can create FRC trebuchets to play Aim High all over again.

Re: Any restrictions on engines?
 

Can we use the batteries as counterweight? Or maybe the pneumatic storage tanks (as long as they're not painted)?

Re: Any restrictions on engines?
 

Well, the search engine does throw a kink into the definition. I think I will call google a search motor from now on.

Re: Any restrictions on engines?
 

So does a siege engine! I don't steam a old train with a steam engine, but I siege a city with a siege engine.

Re: Any restrictions on engines?
 

Combustion Motor - It has moving parts, but the energy source (the gas tank) is not part of it, thus it isn't an engine.

Electric Engine - It has moving parts and electrons are used inside, therefore it IS an engine.

:)

Re: Any restrictions on engines?
 

We use the engines of our imagination on the robot all the time.
FIRST being an engine of change after all.

Re: Any restrictions on engines?
 

It would be possible to argue that a siege engine takes energy from gravity, or "deformation of parts" in order to do work on a projectile

But would that make any gun or bow an engine?

Re: Any restrictions on engines?
 

Obvious troll is obvious.

Had me going for a second though. Well done.

-Nick

Re: Any restrictions on engines?
 

That's what I did.

But not on the robot.